#extension GL_OES_EGL_image_external : require
precision mediump float;
varying vec2 vTextureCoord;
uniform samplerExternalOES sTexture;

void main() {
    vec4 color;


       if (vTextureCoord.x < 0.5) {

           color = texture2D(sTexture, vec2(vTextureCoord.x + 0.5, vTextureCoord.y));
       } else {

           color = texture2D(sTexture, vec2(vTextureCoord.x - 0.5, vTextureCoord.y));
       }

       gl_FragColor = color;
#       // 输出反转后的颜色
}